In various manufacturing processes, small components or articles often need to be securely moved or held in a fixed position during assembly. In order to secure and hold such articles, a vacuum pick up tool can be used. Conventional vacuum pick up tools commonly include an integrated vacuum and purge assembly. In such systems, a vacuum source and a purge gas source are pneumatically coupled to one end of a filter while an end effector for contacting the articles is coupled to the other end of the filter. To pick up an article, the vacuum source is activated and vacuum pressure is thereby created through the filter and at the end effector for picking up the article. To release the article, the vacuum source is usually de-activated and a purge gas source activated thereby creating purge gas pressure through the filter and at the end effector for releasing up the article. The purge gas is typically air.
In some instances however, the air used as the purge gas contains contaminants that are able to bypass the filter and thereby contaminate the article. In addition, in some instances, the surface of the article initially includes a few contaminants that are sucked to the intake side of the filter closest to the end effector when the article is picked up. In such case, when the purge gas source is activated to release the article, the contaminants previously collected at the intake of the filter are expelled back onto the article thereby re-contaminating the article. Accordingly, a vacuum pick up assembly for picking up articles and minimizing contamination of the articles is needed.